Hardware and Software Requirements
At a minimum, your Linux development system should satisfy the minimum requirements indicated in the following table.

Table 3-1 &nbsp&nbsp Hardware and Software Requirements for Linux

Component

Requirements

Operating system

Red Hat Linux 7.1 (or compatible)

CPU

Intel Pentium 166 MHz (or compatible) PC that is TCP/IP networked

RAM

128 Mbytes

Hard drive space

The GNUZIP tar file containing the product is approximately 8 Mbytes.

The installed product requires approximately 8 Mbytes of hard drive space. MQ, however, may need more space if the broker stores persistent messages locally.

JVM

1.4 JVM

The MQ software distribution CD includes the JRE 1.4 version available at the time of release.

Installing MQ on Linux
The Sun ONE Message Queue product can be downloaded from the Sun ONE website or installed from the product CD-ROM. See the appropriate section below for instructions.

Installing from the Web

The following instructions explain how to download and install the MQ product on Linux from the Sun ONE website.

To install MQ on Linux from the Web

Accept the license agreement.

Download the MQ product from the website into an empty, temporary download directory, temp_directory.

The download tar file is: imq3_0-edition-linx86.tar.gz

where edition takes one of the following values: plt or ent, depending on whether you are installing the Platform Edition or Enterprise Edition, respectively.

Uncompress the downloaded file.

gunzip imq3_0-edition-linx86.tar.gz

This creates a single tar file, imq3_0-edition-linx86.tar

Become root on your system:

su root

Change to the /opt directory.

cd /opt

This is the recommended installation directory. If you install MQ into a root_path directory different from /opt, you will have to make the corresponding modifications to the steps that follow.

Untar the archive:

/bin/tar xvfp temp_directory/imq3_0-edition-linx86.tar

The /opt/imq directory and its contents are created.

If you plan to use the broker (see Table 1-2) as a user other than root, change permissions to allow reading and writing to the /opt/imq/var directory:

chmod 777 /opt/imq/var

Back up the imq3_0-edition-linx86.tar.gz file from your temporary working directory.

This is your logical media. Treat this file as you would any other installation media. Place a copy in a safe location in case you encounter a situation (such as a system failure) that requires reinstallation of the product.

Installing from CD-ROM

The following instructions explain how to install the MQ product on Linux from CD-ROM.

Configuring the Java Runtime for MQ
At startup time, a broker (the MQ message server) checks to make sure it has access to the required Java runtime version (JDK/JRE 1.4). There are a number of ways you can configure or set the JRE used by the broker. These are shown in the following list, in order of precedence:

Pass in the JDK or JRE using either the imqbrokerd -javahome or -jrehome command line options, respectively (if both are passed in, the last one on the command line will take precedence).

Set the JDK or JRE in the IMQ_JAVAHOME environment variable.

Let the broker use the installed JDK/JRE. The broker will pick up the latest version JDK/JRE installed on the system (greater than 1.4 and less than 2.0).

The JDK is located in /usr/java/j2sdk1.x.x, and

the JRE is located in /usr/java/j2re1.x.x

To find out why a broker is picking up a specific JDK/JRE, you can start the broker with the following command:

To upgrade from the Platform Edition to the Enterprise Edition, you need to install the Enterprise Edition license. This upgrade does not overwrite the MQ modules already installed and does not modify the configuration of your MQ messaging system.

To install the Enterprise Edition license you need only extract the license file contained in the Enterprise Edition and place it in your MQ installation directory.

If you wish to preserve the MQ flat file user repository and the MQ access control file, copy the following files to some safe location before removing MQ packages (they can be restored after re-installing or upgrading MQ):

IMQ_HOME/etc/passwd

IMQ_HOME/etc/accesscontrol.properties

Become root:

su root

If you want to retain dynamic data for any reason, move /opt/imq/var to a temporary directory:

mv -rf /opt/imq/var /tmp

Remove the MQ product.

Issue the /bin/rm command. For example, if the product is installed in /opt/imq you could type: